Do more robust prescription drug monitoring programs reduce prescription opioid overdose?

BACKGROUND AND AIMS: In the United States, overdose deaths attributed to opioid pain relievers (OPR) have quadrupled since 1999, prompting many states to adopt Prescription Drug Monitoring Programs (PMP). This study aimed to: (1) estimate the relationship of PMP strength with OPR overdose deaths across states and over time; (2) measure what threshold in PMP strength is associated with the greatest reduction in OPR overdose; and (3) assess the relationship of medical marijuana dispensaries with OPR overdose deaths. DESIGN: Panel data from the Centers for Disease Control and Prevention's (CDC's) Wide-ranging Online Data for Epidemiologic Research database (WONDER) were analyzed using fixed effects to regress state-year death rates on an index variable compiled from the Prescription Drug Abuse Policy System (PDAPS) while controlling for PMP administration, demographic factors and laws that might affect OPR overdose. SETTING AND PARTICIPANTS: Age-adjusted opioid overdose death rates for all 50 states and the District of Columbia between 1999 and 2014 for a total of 816 observations. MEASUREMENTS: PMP strength was calculated using legal data compiled by the Prescription Drug Abuse Policy System (PDAPS). In addition to demographic controls, other covariates included laws that regulate pain clinics, access to naloxone, use of emergency services (Good Samaritan Laws) and medical marijuana. FINDINGS: PMP strength was associated negatively with OPR overdose deaths. Every 1-point increase in PMP strength was associated with a 1% 95% confidence interval (CI) = 0.2-2% reduction in overdose deaths. When collapsed into quartiles, PMPs in the third quartile were associated with an approximately 18% (95% CI = 1.6-29%) reduction in OPR overdose death rates compared with states without a PMP. States with medical marijuana dispensaries reported a 16% (95% CI = 1-30%) reduction in OPR overdoses. CONCLUSIONS: US states that have more robust prescription drug monitoring programs have fewer prescription opioid overdose deaths than states with weaker PMPs. States with medical marijuana dispensaries also report fewer opioid overdose deaths than states without these.